I don't have linux running at the moment but I think the gz archive is an executable binary. Shocked Try renaming to gplanarity, changing permissions, and executing from the command line.

Yes indeed I've tried this and gz format is all I can find of it. Petget claims to install it when clicked on but apparently doesn't.. Extracted it but could not find an executable file, couldn't start from command line either. I'll keep working on this one, good learning experience